A11ying with Sanna - Web Content Accessibility Guidelines a guide to the accessibility requirements
3 Understandable

3.2.2 On Input

Conformance level: A
Criterion released in WCAG version: 2.0

Official description of the success criterion

Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component.

What to do?

Ensure changes of context are initiated only on user request.

Why is it important?

Helps users maintain control over their interactions.

Common pitfalls

WCAG Failure F36: Automatically submitting a form and presenting new content without prior warning when the last field field in the form is given a value.

WCAG Failure F37: Launcing a new window without prior warning when the selection of a radio button, check box or select list is changed.

More about this criterion elsewhere